1. Field of the Invention
The present invention relates to a developer container which accommodates a developer, and to a developer supplying device which supplies a developer, such as toner, to a developer receiving device, such as a visible image formation unit that forms a visible image on an image supporting medium such as a photoconductor. Moreover, the present invention relates to an image forming apparatus, such as a copier, a printer, a facsimile, etc., which uses the developer container and the developer supplying device.
2. Description of the Related Art
Conventionally, it is known that a cylindrical toner bottle is used as a developer container which is provided in a developer supplying device which supplies a developer, such as toner, to a developing device of an image forming apparatus, such as a copier, a printer, a facsimile.
The toner bottle is provided with a spiral projection disposed in the inner wall of the toner bottle and a bottle gear for rotating the toner bottle. The developer, such as toner, inside the toner bottle is discharged from the toner bottle by rotation of the toner bottle through the gear, and the discharged developer is conveyed to the developing device, so that the developing device is supplied with the developer.
However, even if the toner guide is provided in the developer container in which the gear is provided on the side surface of the developer container near the opening of the toner, there is the problem that discharging of the toner by the rotation of the developer container in the circumferential direction thereof may not be performed smoothly.
The bottle gear provided in the toner bottle as the developer container is configured in a ring-like formation in which a central opening is formed on the inside peripheral surface of the gear. When the diameter of the opening is smaller than the inner diameter of the inner wall of the toner bottle at the position where the gear is provided, the inner wall of the toner bottle is provided with a raised portion which is raised from the position of the bottle gear.
Since the toner bottle is laid horizontally in the image forming apparatus, if the raised portion of the inner wall is at the intermediate portion before the position where the toner inside the bottle arrives at the toner outlet, the toner inside the bottle cannot be transferred beyond the raised portion and cannot reach the toner outlet. For this reason, there is the case in which discharging of the toner may be performed smoothly.
A conceivable method to overcome the problem is to make the diameter of the opening of the bottle gear larger than the inner diameter of the inner wall of the toner bottle. For example, the diameter of the opening of the gear may be made to equal to the inner diameter of the inner wall of the toner bottle.
However, in such a case, there is a certain amount of distance from the opening of the gear to the dedendum of the gear teeth, and the gear tooth will project from the peripheral side surface of the toner bottle in the direction normal to the bottle peripheral surface. Then, the image forming apparatus in which the toner bottle is provided will require the space for accommodating the bottle gear rotatably inside the apparatus, in addition to the space for accommodating the toner bottle inside the apparatus. This makes the image forming apparatus to be enlarged in size.
Therefore, in order for the miniaturization of the image forming apparatus, it is desirable that toner supply can be performed smoothly even when the diameter of the opening of the bottle gear is smaller than the inner diameter of the inner wall of the toner bottle.
Japanese Laid-Open Patent Application Nos. 10-063084, 07-020705 and 09-251240 disclose some toner bottles which are a developer container and provided to be detachably attached to the toner supply device of the main part of the image forming apparatus in the longitudinal direction of the apparatus. In the conventional devices of the above-mentioned documents, the toner bottle is detachably attached from the front side of the image forming apparatus, or the cartridge accommodating the toner bottle therein is detachably attached from the front side of the apparatus main part.
Moreover, in order to carry out the rotation drive of the toner bottle, the conventional devices of the above-mentioned documents have the following mechanisms.
In the device of Japanese Laid-Open Patent Application No. 10-063084, the bottom of the toner bottle is connected with the drive unit provided on the rear side plate of the apparatus main part so that the rotation drive of the toner bottle is carried out.
In the device of Japanese Laid-Open Patent Application No. 07-020705, the engagement unit provided near the shoulder of the toner bottle is connected with the drive unit provided in the apparatus main part, so that the rotation drive of the toner bottle is carried out.
In the device of Japanese Laid-Open Patent Application No. 09-251240, the bottle gear is provided near an end of the toner bottle opposite to another end of the toner bottle where the toner outlet is formed, and the bottle gear is engaged with the drive gear so that the rotation drive of the toner bottle is carried out.
As described above, in the devices of the above-mentioned documents, the toner bottle or the cartridge which accommodates the toner bottle is detachably attached from the front side of the apparatus main part, and the operation space in the case of the attachment and detachment will be needed at the front side of the apparatus, and it will be necessary to take many installation area of the apparatus.
Moreover, in the composition in which the developer container is detachably attached from the front side of the apparatus main part, the operator has to lean over in front of the apparatus, and has to perform the toner bottle exchange, or in order to detach the used developer container from the apparatus main part in the state where the toner outlet opened, the operator has to consider so that the remaining toner may not leak from the opening and the front of the apparatus may not be polluted.
From the above reasons, the attachment/detachment method of the developer container from the front side of the apparatus must be taken into consideration.
Moreover, it is demanded that the operator can easily perform developer container exchange, with the spread of color image forming apparatuses in recent years, and it is necessary to make the attachment/detachment operation of the developer container easy.
If the developer container can be detachably attached from the upper part of the main part of the apparatus apart from the above conventional method of detaching and attaching the developer containers from the front of the apparatus, what is necessary is opening the top cover of the main part of the apparatus in the case of developer container attachment and detachment, and exchange removing the developer container of the required color from the upper part, and just coming to set the new developer container.
Therefore, it is no longer necessary to take the operation space in the installation area of the apparatus as in the conventional method of attachment and detachment of the developer container from the front of the apparatus, and it is possible to reduce the installation area.
Moreover, since attachment/detachment operation can be performed being able to exchange the developer container, with the operator standing, and looking at the developer container and it is easy to protect that the toner from developer container opening begins to leak, and the attachment/detachment operation becomes easy.
From the above reason, the developer container attachment and detachment from the upper part of the apparatus main part can also make the operation easy, and it is possible to reduce the installation area of the apparatus. This is desirable.
Moreover, although the miniaturization of the apparatus is being called for in recent years, in order to miniaturize the apparatus, what is taken into consideration also about the configuration of the drive unit which drives the developer container is searched for.
However, in the device of Japanese Laid-Open Patent Application No. 10-063084, the engagement unit with the main part side drive unit of the apparatus in the toner bottle is provided in the direction end of the toner bottle length, and the position in which the drive unit is formed consists of this bottle the back side further in the direction of the length of the toner bottle.
For this reason, the total length of the depth of the drive unit and the length of the toner bottle in the longitudinal direction will be needed for the depth of the apparatus, and the length of the apparatus will be enlarged.
If the peripheral side surface of the toner bottle is adjoined as in the devices of Japanese Laid-Open Patent Application Nos. 07-020705 and 09-251240 and the input unit of driving force is provided, the necessity of arranging in order and providing the drive unit and the bottle in the direction of the bottle length will be lost, and it is possible to prevent enlargement of the depth of the apparatus. The apparatus can be miniaturized, and it is desirable.
If the input unit of driving force is provided in the side surfaces other than the direction end of the length of the developer container from the upper part of the apparatus while enabling the developer container attachment/detachment from the apparatus upper part, the advantages of space saving at the time of attachment and detachment, improvement in the attachment/detachment operation, and many further called the miniaturization of the apparatus can be obtained, and the usefulness is high.
Moreover, in the conventional device, the developer container, such as the toner bottle, is provided so that the developer container is detachably attached to a container mounting unit of the developer supplying device.
In the conventional device, after removing the used developer container which is empty with consumption of the developer from the container mounting unit, the developer can be replaced with the image forming apparatus to the developer receiving device, such as the visible image formation unit, by setting the new developer container.
In the above developer supplying device, the developer in the developer container is moved to the outlet as such a developer supplying device using conveyance drive components, such as the agitator provided in the main part of the container, as disclosed in Japanese Laid-Open Patent Application No. 2002-357945.
Moreover, the spiral projection is formed in the inner wall of the elongated main part of the container which accommodates the developer inside, and the internal developer is moved to the outlet by rotating the main part of the container so that the central axis extending in the longitudinal direction may turn into the center-of-rotation axis, as disclosed in Japanese Laid-Open Patent Application No. 2000-338758.
In the developer supplying device of Japanese Laid-Open Patent Application No. 2000-338758, the spiral projection formed in the wall in the main part of the container is moved with the rotation of the main part of the container, and the internal developer is moved to the outlet by the movement of the spiral projection.
Similar to the developer supplying device of Japanese Laid-Open Patent Application No. 2000-338758, the applicant to which the present invention is assigned has proposed the image forming apparatus equipped with the developer supplying device in which the main part of the container is rotated, and the internal developer is moved to the outlet by the rotation of the container main part, as disclosed in Japanese Patent Application No. 2002-276466. Japanese Patent Publication 2004-139031, published on May 13, 2004, claimed priority from Japanese Patent Application 2002-276466, which was abandoned and never published.
In the above-mentioned image forming apparatus, the toner bottle as shown in FIG. 32A, which is a developer container, is used. In the toner bottle 632 of FIG. 32A, the cap portion 634, which is a rotation unit, is provided at the leading end of the main part 633 of the toner bottle 632.
Moreover, the toner outlet (not shown) opens to a part of the peripheral side surface of the cap portion 634, and this toner outlet is closed with the shutter 636 in the state of FIG. 32A. This shutter 636 is attached to the peripheral side surface of the cap portion 634 so that it is slidable on the peripheral side surface of the cap portion 634.
Moreover, in order to allow the cap portion 634 to be rotated around the central axis of the cap portion 634, the handle 635 which is taken by the operator is formed integrally with the cap portion 634. When placing the toner bottle 632 on the bottle holder 631 indicated by the dotted line in FIG. 32A, the toner bottle 632 is laid on the bottle holder 631 as in the state of illustration.
If the direction of the arrow N in FIG. 32A is made to rotate the handle 635, although the cap portion 634 constituted by the handle 635 and one rotates, as for the shutter 636, in contact with shutter stop unit 631a of the bottle holder 631, rotation will be prevented from this state.
Thereby, the shutter 636 carries out the slide transfer relatively to the peripheral side surface of the cap portion 634 by the rotation, and the toner outlet is moved so that it faces the bottle holder 631 in the downward perpendicular direction (the underside of FIG. 32A). Therefore, the toner outlet which is in the closed state by the shutter 636 is opened to the perpendicular direction down side.
On the other hand, when removing the toner bottle 632 from the bottle holder 631, the handle 635 is rotated in the reverse direction opposite to the direction of the arrow N in FIG. 32A.
Thereby, the toner outlet also transfers for reverse with rotation of the cap portion 634 with the arrow N in FIG. 32A, and the shutter 636 carries out the slide transfer relatively to the peripheral side surface of cap portion 34Y according to the energization force by the energization unit (not shown).
And the toner outlet is closed by the shutter 636. Therefore, in case the toner bottle 632 is dealt with, the toner does not begin to leak from the toner outlet.
FIG. 32B is a cross-sectional view of the circumference of the cap portion 634 taken along the central axis O of the toner bottle 632 and passing through the toner outlet.
As shown in FIG. 32B, as the cap portion 634 is inserted in the portion of the opening C of the main part 633 of the bottle, it is attached to the main part 633 of the bottle.
And when the toner bottle 632 is set to the bottle holder 631, this cap portion is locked to the bottle holder. Therefore, when it is engaged with the drive gear of the drive motor and the rotation driving force of the drive motor is transmitted to the bottle main part 633 via the bottle gear 637, the main part 633 of the bottle is rotated in the direction of the arrow Q in FIG. 32A with the friction sliding of the bottle gear 637 with the cap portion 634.
However, the lock of the cap portion 634 to the bottle holder 631 may be made with a comparatively weak force in consideration of the ease of operation of the operator who operates the handle 635 of the cap portion 634.
Therefore, if the frictional force between the rotating main part 633 of the bottle and the cap portion 634 exceeds the force to lock the cap portion 634, the cap portion 634 will rotate with the rotation of the main part 633 of the bottle.
Consequently, the toner outlet opened to the perpendicular direction down side is also moved to the direction of the arrow Q in FIG. 32A, and will be in the closed state by the shutter 636. Then, even if the main part 633 of the bottle is rotated to perform toner supply operation, there is the problem that the situation in which toner supply is not actually performed arises.
In addition, if the direction (the direction of the arrow Q in FIG. 32A) of rotation of the main part 633 of the bottle is reversed, the toner outlet will not be closed according to the friction between the main part 633 of the bottle and the cap portion 634, and the above-mentioned problem does not occur.
However, it is necessary to reverse the direction of the rotation drive of the main part 633 of the bottle in this case and the design change relevant to the composition of the toner feeder and the whole image forming apparatus is obliged, and it may be difficult to adopt such composition.
Moreover, since the direction of the spiral toner guide 633a currently formed in the inner wall of the main part 633 of the bottle in this case must be reversed by the design change, there is also the disadvantage that it is impossible to use the toner bottle before design change.
On the other hand, if the direction (the direction of the arrow N in FIG. 32A) in which the shutter 636 is displaced relative to the cap portion 634 when changing the toner outlet to the closed state is reversed, the above-mentioned problem does not occur.
However, it will be necessary to change the composition of the toner feeder relevant to the shutter in this case, and it may be difficult to adopt such composition.
Moreover, since the cap portion 634 will also be subjected to the composition change in this case, there is also the disadvantage that it is impossible to use the toner bottle before design change.
Moreover, if the toner bottle 632 is provided such that the cap portion (rotation unit) 634 may be rotated in the first direction (which is opposite to the second direction in which the shutter 636 opens the toner outlet), the operator may rotate, when attaching the toner bottle 632 to the bottle holder 631, the cap portion (rotation unit) 634 in the first direction accidentally. In this case, there is the possibility of the incorrect setting of the cap portion 634.
Moreover, if the toner bottle 632 is provided such that the cap portion 634 may be rotated further after the toner outlet is opened by the shutter 636 through the operator's proper rotation of the cap portion 634 in the second direction when attaching the toner bottle 632 to the bottle holder 631, the cap portion 634 will be excessively rotated. In this case, there is the possibility of the falling out of the shutter 636 may arise.